Pin 5 should be connected to ground through a garden variety bonobo monkey. Failure to do so could result in unexpected circuit behaviour, such as excessive cheese consumption. Martin. BTW, the use of siamese-twin lab mice will allow half the device count. ______________________________ Reply Separator _________________________________ Subject: 16f84 bio-emulator Author: pic microcontroller discussion list at Internet Date: 6/12/98 11:57 AM Hi all, I just started work on a PIC 16F84 emulator using 8 lab mice to simulate the latches. Does anybody know about typical delay constants for one inch of the central tail nerve ? Any suggestions for a diet that reduces this time ? Where should I connect pin 5 of the 555s ? Cheers, Karsten